Good advice Raquel, thanks!
VSTS also does the staged comments thing, and I too end up nuking half of mine as I find the answers further down the page or my understanding improves :)
I also find it useful to leave open questions in the remaining comments, typically asking to have decisions explained because I don't 'get it' yet. Finally I check my comments for assumptions of understanding ('surely the input has...') or jumping to my own solution ideas ('why not like this?'), both these help with questions being less dominant, or challenging, which can improve the reviwee's confidence.
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.